1) Field of the Invention
This invention relates to a hub document preparation method for preparing a single structured document of the hub document format such as, for example, an SGML (Standard Generalized Markup Language) document from a plurality of non-structured documents such as, for example, documents prepared on a word processor.
2) Description of the Related Art
Various structured documents are conventionally known and include an SGML (Standard Generalized Markup Language) document and an XML (Extended Markup Language) document in which document contents are represented in a text format excluding layout information and so forth from document data. Such structured documents as an SGML document and an XML document allow definition of a logical structure of the document by adding a mark called tag for identifying the structure of the document and are progressively spread as standard language documents for storage/search or exchange of a document.
FIG. 8 illustrates a structure of an SGML document. In the following, a structured document is described taking an SGML document as an example with reference to FIG. 8.
Generally, an SGML document 20 is composed of an SGML declaration 21 which describes various references such as types of codes used in the document, a DTD (Document Type Definition) 22 which defines mutual relationships of document elements, that is, a document structure, and a document instance 23 representative of document contents.
The DTD 22 defines tags to be applied to elements of the document such as an index, the body of the document, and a list. More particularly, the DTD 22 includes element declarations which define the elements of the document, relationships of inclusion of elements, an order in which the elements are to be arranged, a number of times of appearance of each element and so forth, attribute declarations which define attributes of the elements, entity declarations which declare methods of taking special characters, pictures or the like into the document, and so forth. The DTD 22 allows definitions of memberships, an order of appearance, numbers of times of appearance and so forth of tags in a tree structure.
In order to prepare the SGML document 20, a document structure of the SGML document 20, that is, the DTD 22, is prepared or acquired first, and then the document instance 23 which fits with the DTD 22 is prepared.
The document instance 23 may have a graphic file, which includes graphic information, or a like file attached thereto. In the following description, a file attached to the document instance 23 in this manner is referred to as attachment file.
Upon preparation of the SGML declaration 21 or the DTD 22, various definition contents (declarations and so forth) may be described directly in the SGML declaration 21 or the DTD 22 as described above, or such definition contents may be described in an external file (external entity) 21a or 22a stored in an external area 25 in advance such that the external file 21a or 22a may be designated by the SGML declaration 21 or DTD 22 (external entity declaration).
Though not illustrated in FIG. 8, upon preparation of the document instance 23, document contents of the document instance 23 may be described in an external file in advance so as to allow the external file to be designated by the document instance 23 of the SGML document 20 (external entity declaration) similarly as upon preparation of the SGML declaration 21 or DTD 22.
The external file designated by the external entity declaration by the document instance 23 may have an attachment file attached thereto. In this instance, an external entity declaration for declaring the entity of the attachment file is prepared.
FIG. 9 illustrates a structure of an SGML document (hub document format structured document) 30 of the hub document format. Referring to FIG. 9, contents of an SGML declaration and a DTD are prepared and described in external files (external entities) 31 and 32, respectively, while a plurality of (two in FIG. 9) document contents (document instances) are prepared and described in external files 33a and 33b, respectively, and the external files 31, 32, 33a and 33b are designated (external entity declaration) by a hub document 35 to prepare the single SGML document 30 of a hub document format.
The SGML document 30 of such a hub document format as described above is suitable as a document wherein document contents are described in detail in a great number of parts, for example, such as a maintenance manual or the like, and is generally suitable to combine contents (instances) of a plurality of documents prepared on a word processor or a like document preparing system into a single SGML document such as the SGML document 30.
It is to be noted that an authoring tool in most cases prepares one SGML document by adding an SGML declaration and a DTD to one document instance (one file) as seen in FIG. 8.
Upon preparation of such a hub document 35 as described above, the preparing person first collects a plurality of external files to be included into the SGML document 30 of the hub document format, and then prepares entity declarations (ENTITY statements) for individually referring to the entities of the external files.
However, in such a conventional hub document preparation method as described above, in order to designate the external files with the external entity declarations, the preparing person must collect necessary external files.
For example, in order to designate the external files 31, 32, 33a and 33b, which are discretely located on the computer system and in which document instances and so forth are stored individually, with external entity declarations, the external files 31, 32, 33a and 33b must be located after the stored locations of them are checked. Therefore, the conventional hub document preparation method described above has a subject to be solved in that the operation just described is cumbersome and makes a heavy burden to the preparing person, and besides much time is required for the preparation of the hub document 35 and the operation efficiency is low.
Further, where a document instance has an attachment file such as a graphic file added thereto, in order to prepare an entity declaration (ENTITY statement) for referring to the entity of the attachment file, not only an external file of the document instance must be collected but also the stored location of the attachment file must be checked to collect the attachment file. Consequently, the conventional hub document preparation method described above has another subject to be solved in that the presence of such an attachment file as described above further increases the burden to the preparing person and increasing time is required for preparation of the hub document 35 and besides the operation efficiency is deteriorated.